<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>Document</title>
</head>
<body>

</body>
<script>
// var a  = 10;
// var a  =20;
// console.log(a)

// const a = 10;
// a = 20;
// console.log(a);

const a = {
    name:"张三",
    age:10
}
a.name = "李四";
console.log(a);

// let obj  = {
//     a:10,
//     b:20
// }
// let {a:mya, b} = obj;
// console.log(mya);

// 不定参
// function test(...arg){
//   console.log(arguments);
// console.log(arg);
// }
// test(10,20,30)

// let test = (a)=>a;
// let test = (a)=>{
//     return a;
// }
let test = ()=>({name:"张三",age:20});
console.log(test());

</script>
</html>
